If you couldn't, here are ways to randomize your source port to help mitigate the attack with iptables or pf: http://cipherdyne.org/blog/2008/07/mitigating-dns-cache-poisoning-attacks-with-iptables.html http://blog.spoofed.org/2008/07/mitigating-dns-cache-poisoning-with-pf.html -Vince